Postprocessing of seat belts for adding dye

ABSTRACT

Methods for marking a seat belt webbing with an infrared compound are described herein. The methods comprise ablating a surface of the seat belt webbing by directing one or more laser pulses toward the seat belt webbing; and coating the ablated surface of the seat belt webbing with the infrared compound, wherein the infrared compound increases absorptivity or reflectivity of the seat belt webbing to infrared radiation. Methods for optically monitoring operation of the seat belt webbing in a vehicle and distinguishing between proper positioning and improper positioning of the seat belt webbing are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. provisional patentapplication No. 63/132,705, filed Dec. 31, 2020, and titled“POSTPROCESSING OF SEAT BELTS FOR ADDING DYE,” the disclosure of whichis expressly incorporated herein by reference in its entirety.

TECHNICAL FIELD

The disclosure presented herein relates to optical detection of a seatbelt within a vehicle cabin such as to locate, identify, and highlightseat+belt assemblies therein to confirm seat belt use and seat beltpositions; and more particularly to methods for applying an optical dyeto seat belts to distinguish between different seat belt positions.

BACKGROUND

Seat belts are standard equipment for almost every kind of vehicle inwhich occupants are transported in today's transportation systems. Notonly are original equipment manufacturers (OEMs) required to meet strictstandards for seat belt engineering and installation, but in manyscenarios, vehicle occupants are required to wear seat belts as a matterof law. Even with manufacturing regulations and use laws in place,however, overall vehicle safety is entirely dependent upon vehicleoccupants using seat belts properly. Visual inspection by outsideauthorities is not completely reliable given that a vehicle interior isonly partially visible from outside of a vehicle. Individuals attemptingto circumvent seat belt use laws also position seat belts inside avehicle in a way that gives an appearance of seat belt use but allowsthe vehicle occupant more latitude in range of movement (i.e., fasteningthe seat belt behind the user's back or pulling the seat belt onlypartially across the user's body and manipulating the seat belt spool tomaintain the seat belt in an extended position without requiring a fixedlatching).

Prior methods of seat belt monitoring can be effective but can also bespoofed. As noted above, individuals continue to engage in improper seatbelt buckling behind or under the occupant, attaching buckle surrogateswithout using the seat belt, and maneuvering themselves out of the seatbelt, particularly the shoulder strap, by hand. Furthermore, many rearseating locations do not currently use seat belt switches, belt payoutsensors, or belt tension sensors. It may be difficult to install thenecessary electronics in adjustable and movable seating locations tosupport buckle switches, payout or tension sensors as aftermarketcontrol hardware. Thus, a need continues to exist in the vehicle marketfor control systems that monitor vehicle occupants for proper seat beltuse and provide seat belt use and position data.

In response to that desire, optical imaging systems have been developedthat produced an electronic image of the seating area in the motorvehicle and analyzed that image to detect the presence and size of anoccupant. WO 2020/206456 describes such a motor vehicle occupantdetection system. These systems may use near infrared (NIR) light toilluminate the vehicle, while an image is being acquired.

Currently, seat belts are dyed and sealed with anti-abrasive and/oranti-wicking coatings to prevent damage due to mechanical wear andchemical interactions. While this is good for consumer product that willencounter various chemical and mechanical stresses throughout its life,this specific process of seat belt manufacturing requires significantmodification if anyone wants to make customizations to the seat belt,such as making belt patterns with novel dyes for specific purposes.

A need exists in the vehicle market for development of new seat belt,specifically one which includes patterns with dyes and pigments. A needalso exists for methods of applying dyes and pigments to a manufacturedseat belt. The systems and methods disclosed herein address these andother needs.

BRIEF SUMMARY

Methods for marking a seat belt webbing with an infrared compound areprovided herein. The methods can comprise ablating a surface of the seatbelt webbing by directing one or more laser pulses toward the seat beltwebbing; and coating the ablated surface of the seat belt webbing withthe infrared compound, wherein the infrared compound increasesabsorptivity or reflectivity of the seat belt webbing to infraredradiation. The seat belt webbing is typically a woven textile.

The seat belt webbing can be derived from polyamide, polyolefin,polyester, polyether, polycarbonate, polyurethane, or a combinationthereof. In example embodiments, the seat belt webbing is derived frompolyester.

The seat belt webbing can comprise a pre-coat rendering the seat beltwebbing waterproof and/or anti-abrasive. For example, the seat beltwebbing can include a pre-coat of a polymer elastomer, such as silicone,a polyester or polyether-based polyurethane, a polycarbonate-basedpolyurethane, a copolymer blend of ethylene vinyl acetate and anisocyanate, or a combination thereof. The pre-coat can have a thicknessof about 0.1 mil or greater.

As described herein, the surface of the seat belt webbing is ablatedusing one or more laser pulses. The method can comprise directing theone or more laser pulses to ablate the seat belt webbing in apredetermined pattern.

The infrared compound used to coat the ablated surface can be selectedfrom an infrared absorptive compound, an infrared reflective compound,or the infrared compound absorbs and reflects infrared light. Theinfrared compound can be provided in a carrier selected from vinylprinting ink, acrylic lacquer, polyurethane, or polyurethane lacquer.Coating the ablated surface of the seat belt webbing can be performed bya rolling mill, roller, brush, mask, dip coating, spin coating, and/orspray coating. The coating can be applied in a predetermined pattern.Preferably, the seat belt webbing maintains greater than 95% of itstensile strength, elongation, mass, width, thickness, curvature,colorfastness, or a combination thereof, after marking with the infraredcompound.

Methods for optically monitoring operation of a seat belt webbing arealso provided. The methods can comprise illuminating the seat beltwebbing with electromagnetic radiation using at least one illuminationdevice, wherein the seat belt webbing is marked with an infraredcompound as disclosed herein and has at least one pattern that absorbsor reflects the electromagnetic radiation; obtaining images of theilluminated seat belt webbing using at least one image obtaining device;and analyzing the images to determine proper positioning of the seatbelt webbing relative to an occupant or derive a measure of theoccupant's vital signs.

The pattern may comprise a size, shape, or absorptiveness/reflectivityconfigured to distinguish various patterns in the images. In exampleembodiments, the presence in the image of a pre-determined patternindicates the seat belt webbing relative to the occupant within thevehicle is properly positioned. In other example embodiments, theabsence in the image of a pre-determined pattern indicates the seat beltwebbing relative to the occupant within the vehicle is improperlypositioned.

Analyzing the images can comprise comparing at least two images andtracking movement of the seat belt webbing. Accordingly, vital signssuch as a respiration rate of the occupant can be monitored over timeand a determination of whether the occupant has an irregular respirationrate can be made. The occupant can be a driver and the method cancomprise analyzing the driver's respiration rate over time to determinewhether the driver has lost the ability to continue to control thevehicle.

In the methods of optically monitoring operation of the seat belt, themethods can further comprise triggering an alarm within the vehiclebased on the positioning of the seat belt webbing relative to theoccupant or the occupant's vital signs.

Methods by which a camera image system in a vehicle distinguishesbetween proper positioning and improper positioning of a seat beltwebbing are also disclosed. The method can comprise marking the seatbelt webbing with an infrared compound as disclosed herein, wherein themark comprises at least one pattern that absorbs or reflectselectromagnetic radiation; producing an image in response to infraredradiation absorbed or reflected by the seat belt webbing relative to anoccupant within the vehicle; and distinguishing between the properpositioning and improper positioning of the seat belt webbing in theimage based on the at least one pattern. The presence of apre-determined pattern in the image indicates the seat belt webbing isproperly positioned relative to an occupant within the vehicle, andabsence of the pre-determined pattern in the image indicates improperpositioning of the seat belt webbing.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an intensity image showing the pattern of light reflected froma seat belt from just etching the surface sealant off the webbing.

FIG. 2 is a depth image showing the even depth of a seat belt with apattern etched onto the surface.

FIG. 3 is an image showing a dyed seat belt pattern having an X and abox.

FIG. 4 is an image showing a dyed seat belt pattern having a largemiddle region to be dyed surrounded by an unetched region at the edgesof the seat belt along with a schematic illustration of a laserproducing laser pulses to ablate the surface of the seat belt webbing,according to one implementation.

FIG. 5 is an image showing a dyed seat belt with two repeated patternsand showing the feasibility of aligning the seat belt after a singlepattern is etched on the surface.

FIG. 6 is an image showing a vehicle occupant with a dyed seat belt inuse in view of cameras in the vehicle.

FIG. 7 is a flowchart depicting a method for marking an example seatbelt webbing with an infrared compound, according to one implementation.

FIG. 8 is a cross section of a seat belt webbing, not drawn to scale,showing the surface roughness details, according to one implementation.

DETAILED DESCRIPTION

This disclosure relates to seat belt webbings and methods for marking aseat belt webbing with an infrared compound. The infrared compoundincreases absorptivity and/or reflectivity of the seat belt webbing toinfrared radiation but does not substantially alter absorptivity orreflectivity of the seat belt webbing to visible light. Illumination ofthe infrared compound allows operation of an occupant detection systemto determine proper seat belt positioning relative to an occupant.

By using manufactured seat belt webbings for marking with the infraredcompound, various mechanical, chemical, and absorptive properties mayalready be secured, which do not facilitate applying new markings on theseat belt. The term “manufactured” as used herein refers to a seat beltwebbing which has been modified to improve the webbing's mechanicalproperties such as abrasion resistance, chemical resistance, heat andlight resistance, anti-wicking or water proofing properties, frictionalresistance, impact absorption, lubricating properties, strengthretention, or a combination thereof. Disclosed herein are methods forapplication of markings to a seat belt webbing, preferably amanufactured seat belt webbing.

In general, the seat belt webbing for marking is a woven textile. Thewebbing can be in the form of a plain weave, a twill weave, a satinweave, a Raier loom, an air jet loom, a water jet loom, or the like.

The seat belt webbing can be derived from any suitable material,including polyamides, polyolefins, polyesters, polyethers,polycarbonates, polyurethanes, or a combination thereof. In someinstances, polyester represented by polyethylene terephthalate (PET) isused as a main component for the seat belt webbing. The yarn for theseat belt webbing should, of course, maintain high strength, and itshould also have good sliding efficiency after being manufactured into aseat belt. The seat belt webbing can have any number of woven yarns,such as 500 yarns/inch or less, 400 yarns/inch or less, or 300yarns/inch or less, upon manufacturing a seat belt. For example, a seatbelt can be made of 320 ends of 1,100 dtex polyester each. In case ofnylon seat belts, 260 ends of 1670 dtex yarn can be used.

As discussed herein, the seat belt webbing prior to marking has improvedmechanical properties, abrasion resistance, anti-wicking or waterproofing properties, strength retention, frictional resistance, heatresistance, impact absorption, and lubricating properties, compared tothe raw materials used to manufacture the seat belt webbing. Forexample, during the preparation of the seat belt webbing, variousadditives may be added in order to secure one or more mechanical,abrasion, water-proofing, heat resistance, impact absorption, orlubricating properties upon being manufactured into a seat belt. In someinstances, the seat belt webbing includes a pre-coat comprising one ormore additives rendering one or more desirable properties to the seatbelt webbing.

The additives may be included in an amount of 30% by weight or less, 25%by weight or less, 20% by weight or less, 15% by weight or less, 10% byweight or less, 8% by weight or less, 6% by weight or less, or 5% byweight or less, based on the weight of the seat belt webbing. In somecases, the additives may be included in an amount of from 1% to 30% byweight, from 2% to 30% by weight, from 5% to 25% by weight, from 10% to30% by weight, based on the weight of the seat belt webbing.

Particularly, the seat belt webbing may include one or more inorganicadditives selected from the group consisting of TiO₂, SiO₂, BaSO₄, andthe like. A non-water based emulsion for maximizing surface lubricitythrough a physical or chemical bond on the webbing surface can beincluded. The non-water based emulsion may include one or more selectedfrom the group consisting of, polydimethylsiloxane, polydibutylsiloxane,polymethylphenylsiloxane, a paraffin-based lubricant, an ester-basedlubricant, a nonionic activator, and an anionic activator. To improvethe friction and wear resistance of the seat belt webbing, materialssuch as a polyketone, silicon, polytetrafluoroethylene (PTFE), calciumcarbonate (CaCO₃), maleic acid, molybdenum, glass fiber, magnesiumstearate, or a combination thereof can be used. Other suitable additivescan include a polymer elastomer, such as silicone, a polyester orpolyether-based polyurethane, a polycarbonate-based polyurethane, acopolymer blend of ethylene vinyl acetate and an isocyanate, or acombination thereof.

As described above, the additive can be in the form of a pre-coat on theseat belt webbing (e.g., shown as 410 in FIG. 4 ) and has a thickness ofabout 0.1 mil or greater, such as 0.15 mil or greater, 0.2 mil orgreater, 0.25 mil or greater, or 0.3 mil or greater.

FIG. 7 shows a method 700 of marking the seat belt webbing 406 with aninfrared dye, and FIG. 4 shows a schematic of a system for carrying outthe ablation step of method 700. The method 700 begins at step 702 withablating a surface of the seat belt webbing 406 to accelerate wear ofthe webbing. Ablating the surface of the webbing 406 can be carried outin a manner to produce a desired ablated pattern (e.g., shown as pattern408) or such that the entire surface of the seat belt webbing isablated. Preferably, the ablating technique includes the use of a laser402. In some embodiments, the method of the present disclosure includesablating the surface of the seat belt webbing 406 by directing a laserbeam 404 produced by a laser 402 onto the webbing surface. As usedherein, laser ablation refers to the process of removing material from asolid surface by irradiating it with a laser beam 404. At low laserflux, the material may be heated by the absorbed laser energy andevaporate, sublimate, or otherwise be separated from the surface byexposure to laser energy, preferably in the presence of a gas flow. Athigh laser flux, the material can be converted to a plasma. Usually,laser ablation refers to removing material with a pulsed laser, but itis possible to ablate material with a continuous wave laser beam if thelaser intensity is high enough.

The depth over which the laser energy is absorbed, and thus the amountof material removed by a single laser pulse depends on a number offactors including, but not limited to, the material's optical propertiesand the laser wavelength and pulse length. The total mass ablated fromthe seat belt webbing per laser pulse is referred to as the ablationrate. Features of laser radiation such as laser beam scanning velocityand the covering of scanning lines can significantly influence theablation process. Laser pulse can vary over a wide range of durations(milliseconds to femtoseconds) and fluxes, and can be preciselycontrolled. The simplest application of laser ablation is to removematerial from the seat belt webbing in a controlled fashion; very shortlaser pulses remove material so quickly that the surrounding materialabsorbs very little heat. The technique of ablating the seat beltwebbing surface with a laser has advantages including high speedoperation, easily automated operation, low cost, high precision, localtreatment, and minimal target heating.

Types of lasers that can be used for ablating the set belt surface inthe present disclosure include, but are not limited to, helium-neonlasers, argon lasers, krypton lasers, xenon ion lasers, nitrogen lasers,carbon dioxide (CO₂) lasers, carbon monoxide lasers, excimer lasers,hydrogen fluoride lasers, deuterium fluoride lasers, chemicaloxygen-iodine lasers, all gas-phase iodine lasers, dye lasers, rubylaser, yttrium-aluminum-garnet (YAG) lasers (e.g. YAG and any of Nd, Cr,Er, Y, Ca, glass, Th, Yb, Ho), and the like. In a preferred embodiment,the seat belt webbing is ablated by directing a laser beam produced by aCO₂ laser onto the webbing surface. In one embodiment, the CO₂ laserproduces a laser beam of infrared light having an operation wavelengthof 1 micron or greater, such as from 1 micron to 25 microns, from 1micron to 12 microns, or from 5 microns to 12 microns. The laser beamproduced by the CO₂ laser has a diameter of at least 100 μm, at least150 μm, at least 200 μm, up to 400 μm.

The ablating can be performed by directing a laser beam produced by alaser with a pulse frequency of 1200 Hz, or greater, such as 1200 to5000 Hz, such as 1200 to 1800 Hz, or 1200 to 3000 Hz onto the seat beltwebbing. As used herein, pulse frequency refers to a measure of thenumber of cycles of emitted light per second, with each cycle of emittedlight (“on time”) being separated by intermittent “off time.” As usedherein, duty indicates the on/off ratio of the laser beam for every onecycle. A higher duty indicates that the laser has a higher ratio of “ontime” compared to “off time.” In the present method, the laser may havea duty of 20 to 90%, 30 to 80%, 40 to 70%, or 45 to 65%.

The seat belt webbing can be ablated with a laser beam having a power inthe range of 1.5 kW or greater, such as 1.5 to 2.5 kW, 1.6 to 2.4 kW or1.7 to 2.3 kW. In some embodiments, the seat belt surface can be ablatedwith a laser beam with a scanning speed of 0.01 ms' or greater, such asin the range of 0.01 to 5 ms⁻¹, from 0.05 to 1 ms⁻¹, from 0.05 to 0.5ms⁻¹, or from 0.05 to 0.2 ms⁻¹. The pulse width can be 0.1 femtosecondor greater, such as 0.1 femtosecond to 5 seconds, 0.1 femtosecond to 1second, 10 femtoseconds to 0.1 second, or 10 femtoseconds to 1millisecond.

The seat belt webbing can be ablated with a laser beam having apenetration depth of 0.1 μm or greater, such as from 0.1 μm to 1 mm,from 0.1 μm to 0.5 mm, from 0.1 to 100 μm, from 0.1 to 10 μm, from 0.1to 8 μm, from 0.1 to 5 μm. In some embodiments, the laser beampenetration depth is shallow in order to form ablated surfaces with a“low roughness,” as well as to maintain the mechanical and structuralintegrity (such as tensile strength, elongation, mass, width, thickness,curvature, and colorfastness) of the seat belt webbing prior toablation.

As used herein, surface roughness, or roughness, refers to a componentof surface texture. It is quantified by the deviations in the directionof the normal vector of a real surface from its ideal form. If thesedeviations are large, the surface may be considered “rough” and if theyare small, the surface may be considered “smooth.” In some cases, theablated seat belt webbing surface can have a surface roughness of 0.05μm or greater, such as in the range of 0.05 to 0.80 μm.

FIG. 8 shows an example cross section of a seat belt webbing 800 showingthe surface roughness details. FIG. 8 is not drawn to scale—instead, thedetails of the surface roughness resulting from a laser-ablated surfaceare exaggerated for visibility. As shown, a laser pulse 804 is directedtowards a surface 802 of the seat belt webbing 800 resulting in anablated surface 806. The ablated surface 806 includes grooves 808 whichare the deviations in the direction of the normal vector of the surface802 from an ideal form. The ablated surface 806 includes a variedpattern of grooves 808 with some grooves having a depth of 0.05 μm orgreater. The laser pulse 804 has a penetration depth of 0.1 μm orgreater.

Preferably, the seat belt webbing maintains greater than 95% of itsstructural integrity after ablating with the laser. Particularly, theseat belt webbing maintains greater than 95% tensile strength,elongation, mass, width, thickness, curvature, and colorfastness, afterablating with the laser.

The laser acts like a printer and “prints,” “marks,” or “burns” anablated pattern (specified by input file) onto the seat belt webbing.The areas of the seat belt webbing exposed to the laser beam (e.g.,infrared beam) is ablated at a specified position by a certain amountbased on the laser power, time of exposure, and waveform used. The lasercontinues from position to position until the ablated pattern (e.g.,pattern 408) is completely printed on the seat belt webbing. Step 702 ofthe method 700 can comprise directing the one or more laser pulses toablate the seat belt webbing in a predetermined pattern.

Other means for ablating the surface of the seat belt webbing includessandblasting or using sandpaper. For example, some portions or localizedareas of the seat belt webbing are sanded to ablate the webbing surface.

Ablation results in removal of anti-abrasion and/or anti-wickingcoatings that may be present on a surface of the seat belt webbing.Depending on the amount of the anti-abrasion and/or anti-wicking coatingremoved, the dyeing properties of the seat belt webbing will vary.

The method of marking the seat belt webbing with an infrared dye cancomprise coating the ablated surface of the seat belt webbing with theinfrared compound, which is shown as step 704 in FIG. 7 . With laserfinishing, an infrared compound can be applied onto the seat beltwebbing that will appear similar to or indistinguishable from a seatbelt webbing obtained using traditional processing techniques.

The infrared compound can be an infrared absorptive compound, aninfrared reflective compound, or the infrared compound absorbs andreflects infrared light. The infrared compound can be provided in acarrier, such as a polymeric carrier such as a vinyl printing ink,acrylic lacquer, polyurethane, or polyurethane lacquer. To absorb orreflect a specific wavelength, the coating can have varying relativethicknesses. Alternately, the specific infrared dye can be used toabsorb or reflect a specific wavelength. In some embodiments, theinfrared compound can be provided as a coating that has an averageabsorptivity or reflectivity of at least 50%, preferably at least 70%,and more preferably at least 90%, over at least a 100 nm wide band in awavelength region of interest. The wavelength region of interest mayvary widely depending on the specific infrared compound used. Theinfrared coating can absorb or reflect light in the near infraredportion of the spectrum, within the range of 700 nm to 10,000 nm, orfrom 700 nm to 2000 nm.

The infrared compound can be coated on the ablated surface of the seatbelt webbing using any suitable method. For example, the infraredcompound can be applied by using a punch, rolling mill, roller, dipcoating, spin coating, brush, mask, spray coating, or a combinationthereof. The infrared compound can be applied in a predetermined patternto the seat belt webbing.

The seat belt webbing maintains greater than 95% of its structuralintegrity after marking with the infrared compound. For example, theseat belt webbing can maintain greater than 95% of its tensile strength,elongation, mass, width, thickness, curvature, and colorfastness aftermarking with the infrared compound.

This disclosure also uses electromagnetic sensor(s) to detect positionsof a seat belt derived from a seat belt webbing described herein andmonitor (track) seat belt use within a vehicle. The term “vehicle” asused herein includes all of the broadest plain meanings for the termwithin the context of transportation (i.e., any references to anautomobile are for example purposes only and do not limit thisdisclosure to any one embodiment). In one embodiment, the sensor is avideo camera that is responsive to light absorbed or reflected by theseat belt after irradiation by one or more light sources. As describedherein, the seat belt webbing can comprise an infrared compound thatabsorbs and/or reflects infrared radiation in the 700 to 10,000 nmrange, which is invisible to the human eye. In one embodiment, thesensor can be an active optical 3-D imaging system which emits and isresponsive to infrared light which is collocated and/or synchronizedwith a 2-D imager detector array where the amplitude of the detectedsignal is proportional to the absorbed or reflected light. For example,the image may be processed using the optical 3-D time of flight imagingsystem described in WO 2020/206456, which is hereby incorporated byreference in its entirety. Using well known techniques, the sensor cancollect absorbed or reflected light intensity of surfaces in the fieldof view of the imaging system and the distance of the surface from theimage detector.

In some embodiments, a camera utilizing infrared light can be used toilluminate the seat belt webbing and provide absorptive or reflectivelight signals back to an image sensor. The images produced by the imagesensor can be applied to a video input circuit of an image processor.Analysis of the acquired electronic images can be controlled by amicrocomputer. The microcomputer can also operate the infrared lightcontrol circuit which activates the infrared light source while an imageis being acquired from the camera. The detected images can also beprocessed to construct 3-D information (intensity image and depth image)which can be used in machine vision algorithms to detect, and/orclassify, and/or track information about the seat belt use within thevehicle.

In example embodiments, the image processing can determine the presenceof an occupant on the vehicle seat, the size of that occupant, theproper positioning of the seat belt relative to the occupant, derive ameasure of the occupant's vital signs, or a combination thereof. Thatdistinction can be accomplished by coating the seat belt with aninterchanging pattern of infrared compound. The pattern can beconfigured to exhibit various sizes, shape, absorptivity, orreflectivity for optimal contrast to detect/monitor the seat belt use.In cases where the seat belt may be obscured by occupant appendages,objects brought into a vehicle by the occupant, such as clothing,blankets, luggage, cargo, or anything that the occupant places over anexpected area for a seat belt can be accounted for in this system. Forexample, the presence in the image of a pre-determined pattern canindicate the seat belt relative to the occupant within the vehicle isproperly positioned. The absence in the image of a pre-determinedpattern can indicate the seat belt relative to the occupant within thevehicle is improperly positioned. The absence of an image or portions ofan image can indicate the seat belt is obscured.

In further examples, the images can be used in measurement and analysesto track seat belt movement. For example, the method can includecomparing at least two images to determine a respiration rate of theoccupant over time and determine whether the occupant has an irregularrespiration rate. The occupant can be a driver and the method comprisesanalyzing the driver's respiration rate over time to determine whetherthe driver has lost the ability to continue to control the vehicle(e.g., from the driver becoming drowsy, falling asleep, stroke, heartattack, or otherwise being incapable of controlling the vehicle).

The patterns are designed of materials having a knownabsorptivity/reflectivity such that the pattern is distinguishable in anintensity and/or distance image taken of the vehicle interior. A patternhaving a pre-determined absorptivity/reflectivity due to its materialcomposition shows up with a distinguishable luminance sufficient todistinguish the pattern from other structures in an image. The patternmay show up in an image as either a lower luminance region or a higherluminance region at the preference of the designer and continue to beuseful for detecting and monitoring seat belt use. FIGS. 3-5 showexamples of belt pattern for use in monitoring seat belt use. Inparticular, FIG. 5 shows a dyed seat belt 500 with two repeated patternshaving reflective sections 502 and absorptive sections 504. The patternof pre-determined absorptivity/reflectivity is based upon the particularinfrared compound used to dye the seat belt webbing (e.g., an infraredcompound that either increases absorptivity or reflectivity of the seatbelt webbing to infrared radiation).

FIG. 6 shows one example embodiment of a seat belt in use within avehicle interior, and having an occupant therein. The image of FIG. 6illustrates an example of one kind of image that a vehicle camera (or anappropriate system of multiple cameras) can produce from a properlytuned light source illuminating the vehicle interior. As describedherein, the image may be either a two dimensional or three-dimensionalimage, depending on the camera, the array, and the associated computerprocessors, but the patterns on the seat belts, anchor points, andretractors are visible therein.

Many traits of an occupant are currently identified by an occupantclassification system (“OCS”) to assist in controlling air bagdeployment as well as other restraint systems, alerts, and operationalcontrol signals. In non-limiting embodiments of this disclosure, imagesgathered pursuant to the methods and systems herein may be used inconjunction with an OCS to identify proper seat belt placement for manydifferent levels of human development (e.g., adult, child, infant) aswell as anatomy structures (large male, average male or female, smallfemale). Optimal seat belt placement for these diverse occupants will besignificantly different for each. An OCS may receive data from thecomputerized imaging systems described herein to conduct edge analysesto detect occupant forms, 3-D depth analyses for torso position, andanatomical dimensioning for seat belt confirmation relative to theoccupant's body. Single camera and multi-camera systems for both seatbelt monitoring and occupant classification are well within the scope ofthis disclosure. The data collected can then be used to prepare andissue associated alerts or warnings to the occupants, control air bagsand other restraint systems, and update data to help an OCS verifyclassifications of occupants in the vehicle.

Although the present disclosure has been described in detail withreference to particular arrangements and configurations, these exampleconfigurations and arrangements may be changed significantly withoutdeparting from the scope of the present disclosure. For example,although the present disclosure has been described with reference toparticular communication exchanges involving certain network access andprotocols, network device may be applicable in other exchanges orrouting protocols.

Numerous other changes, substitutions, variations, alterations, andmodifications may be ascertained to one skilled in the art and it isintended that the present disclosure encompass all such changes,substitutions, variations, alterations, and modifications as fallingwithin the scope of the appended claims. The structures shown in theaccompanying figures are susceptible to 3-D modeling and can bedescribed relative to vertical, longitudinal, and lateral axesestablished with reference to neighboring components as necessary.

Note that in this Specification, references to various features (e.g.,elements, structures, modules, components, steps, operations,characteristics, etc.) included in “one embodiment”, “exampleembodiment”, “an embodiment”, “another embodiment”, “some embodiments”,“various embodiments”, “other embodiments”, “alternative embodiment”,and the like are intended to mean that any such features are included inone or more embodiments of the present disclosure, but may or may notnecessarily be combined in the same embodiments. Note also that an“application” as used herein this Specification, can be inclusive of anexecutable file comprising instructions that can be understood andprocessed on a computer, and may further include library modules loadedduring execution, object files, system files, hardware logic, softwarelogic, or any other executable modules.

In example implementations, at least some portions of the activities maybe implemented in software provisioned on networking device. In someembodiments, one or more of these features may be implemented incomputer hardware, provided external to these elements, or consolidatedin any appropriate manner to achieve the intended functionality. Thevarious network elements may include software (or reciprocatingsoftware) that can coordinate in order to achieve the operations asoutlined herein. In still other embodiments, these elements may includeany suitable algorithms, hardware, software, components, modules,interfaces, or objects that facilitate the operations thereof.

Furthermore, computer systems described herein (and/or their associatedstructures) may also include suitable interfaces for receiving,transmitting, and/or otherwise communicating data or information in anetwork environment. Additionally, some of the processors and memoryelements associated with the various nodes may be removed, or otherwiseconsolidated such that single processor and a single memory element areresponsible for certain activities. It is imperative to note thatcountless possible design configurations can be used to achieve theoperational objectives outlined here. Accordingly, the associatedinfrastructure has a myriad of substitute arrangements, design choices,device possibilities, hardware configurations, software implementations,equipment options, etc.

In some example embodiments, one or more memory elements (e.g., memory)can store data used for the operations described herein. This includesthe memory being able to store instructions (e.g., software, logic,code, etc.) in non-transitory media, such that the instructions areexecuted to carry out the activities described in this Specification. Aprocessor can execute any type of computer readable instructionsassociated with the data to achieve the operations detailed herein inthis Specification. In one example, processors (e.g., processor) couldtransform an element or an article (e.g., data) from one state or thingto another state or thing. In another example, the activities outlinedherein may be implemented with fixed logic or programmable logic (e.g.,software/computer instructions executed by a processor) and the elementsidentified herein could be some type of a programmable processor,programmable digital logic (e.g., a field programmable gate array(FPGA), an erasable programmable read only memory (EPROM), anelectrically erasable programmable read only memory (EEPROM)), an ASICthat includes digital logic, software, code, electronic instructions,flash memory, optical disks, CD-ROMs, DVD ROMs, magnetic or opticalcards, other types of machine-readable mediums suitable for storingelectronic instructions, or any suitable combination thereof.

These devices may further keep information in any suitable type ofnon-transitory storage medium (e.g., random access memory (RAM), readonly memory (ROM), field programmable gate array (FPGA), erasableprogrammable read only memory (EPROM), electrically erasableprogrammable ROM (EEPROM), etc.), software, hardware, or in any othersuitable component, device, element, or object where appropriate andbased on particular needs. Any of the memory items discussed hereinshould be construed as being encompassed within the broad term ‘memoryelement. Similarly, any of the potential processing elements, modules,and machines described in this Specification should be construed asbeing encompassed within the broad term “processor.”

The invention claimed is:
 1. A method for marking a seat belt webbingwith an infrared compound, comprising: ablating a surface of the seatbelt webbing by directing one or more laser pulses toward the seat beltwebbing; and coating the ablated surface of the seat belt webbing withthe infrared compound, wherein the infrared compound increasesabsorptivity or reflectivity of the seat belt webbing to infraredradiation; wherein the one or more laser pulses have a penetration depthof 0.1 μm or greater, thereby giving the seat belt webbing a surfaceroughness of 0.05 μm or greater, and wherein the seat belt webbingmaintains greater than 95% of its tensile strength after coating withthe infrared compound.
 2. The method of claim 1, wherein the seat beltwebbing is a woven textile.
 3. The method of claim 1, wherein the seatbelt webbing is derived from polyamide, polyolefin, polyester,polyether, polycarbonate, polyurethane, or a combination thereof.
 4. Themethod of claim 1, wherein the seat belt webbing comprises a pre-coat torender the seat belt webbing waterproof and/or anti-abrasive.
 5. Themethod of claim 4, wherein the pre-coat is a polymer elastomer, furtherwherein the polymer elastomer comprises silicone, a polyester orpolyether-based polyurethane, a polycarbonate-based polyurethane, acopolymer blend of ethylene vinyl acetate and an isocyanate, or acombination thereof.
 6. The method of claim 1, further comprisingdirecting the one or more laser pulses to ablate the seat belt webbingin a predetermined pattern.
 7. The method of claim 6, wherein theinfrared compound is applied in a predetermined pattern to the seat beltwebbing.
 8. The method of claim 1, wherein the infrared compound is aninfrared absorptive compound.
 9. The method of claim 1, wherein theinfrared compound is an infrared reflective compound.
 10. The method ofclaim 1, wherein the infrared compound absorbs and reflects infraredlight.
 11. The method of claim 1, wherein coating the ablated surface ofthe seat belt webbing is performed by using a rolling mill, roller,brush, mask, dip coating, spin coating, and/or spray coating.
 12. Themethod of claim 1, wherein the infrared compound is provided in acarrier selected from vinyl printing ink, acrylic lacquer, polyurethane,or polyurethane lacquer.
 13. The method of claim 1, wherein greater thanone laser pulse is directed at the seat belt webbing.
 14. The method ofclaim 1, wherein the one or more laser pulses has an operationwavelength of 1 micron or greater.
 15. The method of claim 1, whereinthe one or more laser pulses is directed to the seat belt webbing with apulse frequency of 1200 Hz or greater.
 16. The method of claim 1,wherein the one or more laser pulses is produced by a CO₂ laser.
 17. Themethod of claim 1, wherein the one or more laser pulses is produced by alaser with a duty of 20 to 90%.
 18. The method of claim 1, wherein thepenetration depth is 0.1 μm to 1 mm.
 19. The method of claim 1, whereinthe surface roughness is 0.05 μm to 0.8 μm.